This project will develop, field and place in the public domain, a longitudinal data set of older adults that reflects the state-of-the art with respect to health and social science surveys of aging. The study will be implemented in Mexico, a rapidly changing, low income society. We will develop a series of innovative modules for older adults, which will be incorporated into a broader survey of adults of all ages, and thereby develop an enriched data base that is specifically designed to capture important dimensions of the health and well-being of the elderly over the life course. Older respondents will be drawn from participants in the Mexican Family Life Survey (MxFLS) an ongoing nationally-representative longitudinal survey of individuals, household, families and communities of over 35,000 people interviewed in 2002 and again in 2005. Additional resurveys will be conducted in 2008 and 2011. With support from this project, over 11,000 respondents age 40 and older will be individually assessed in 2008 and 2011 to form the Mexican Longitudinal Survey of Older Adults and their Families, MxLSOAF. This will yield observations at four points in time spanning nearly a decade of the respondents' lives since most of them were interviewed in the first two waves of MxFLS. In 2008 and 2011, respondents will provide detailed information on health status and health care, work and earnings, pensions, public transfers, kin networks and transfers among network members including non co-resident kin; wealth, migration and living arrangements along with new measures of expectations, attitudes and preferences designed for this project. To complement this information, an innovative set of biomarkers collected from every older respondent will measure risk factors associated with the metabolic syndrome which is a key concern in Mexico where the prevalence of obesity, cardio-vascular disease and diabetes rivals that in the U.S. The data will yield uniquely rich information on older adults in Mexico, reflecting their current and past decisions, which can be linked with information about all household members and non co-resident family across the entire age spectrum. The data are ideally suited to test novel hypotheses about the behavior or older adults as well as evaluate new public programs intended to improve the well-being of Mexico's older population. In the parent project, all movers within Mexico and those who move to the U.S. are followed and interviewed which provides unparalleled opportunities to examine the impact of one's own migration, and that of other family members, on the health and well-being of older Mexicans. MxLSOAF is designed to be comparable with on-going data collection activities in the U.S., U.K., Europe and elsewhere. The project will thereby contribute significantly to the development of public health data infrastructure necessary for scientific research on global aging across substantially different contexts. New longitudinal data on the health and well-being of older adults in Mexico will be developed and placed in the public domain for use by the entire scientific community. These data will not only provide important new insights into the health of older Mexicans but also significantly contribute to the research infrastructure necessary to better understand the implications of global aging for current and future public health policy.